Government auditors slammed the National Oceanic and Atmospheric Administration (NOAA) Thursday for spending billions of dollars on critical satellite systems that have suffered huge delays and technical challenges.

The Government Accountability Office says NOAA environmental satellite systems are “critical to the United States’ ability to maintain the continuity of data required for weather forecasting.” NOAA was supposed to have launched $10.9 billion Geostationary Operational Environmental Satellite-R back March 2016, but now the satellite system will launch months later than was planned.

GAO found the “the decision to delay the launch was due to poor schedule performance over the last few years (losing more than 10 days a month on average), recent technical issues with key components, and little schedule margin as the program entered integration testing.”

Auditors noted the “October 2016 launch date may also be delayed if additional technical challenges arise or if schedule performance remains poor.”

But that’s not all. NOAA’s also having problems with its $11.3 billion Joint Polar Satellite System program that’s scheduled to launch in March 2017. GAO found that while NOAA is making progress on the project it “has experienced technical issues that have affected internal schedule deadlines.”

These technical issues include “an issue with debris in an instrument’s subsystem that delayed its delivery by approximately 8 months, and faces key risks in the remainder of development.”

A Commerce Department inspector general report from June found that NOAA’s GOES-R satellite system was supposed to launch in October 2014, but delays could leave “GOES on-orbit constellation without a backup satellite for 29 months out of a 33-month period from April 2015 to January 2018.”